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1.
Dent J (Basel) ; 8(4)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007807

RESUMO

The purpose of this study was to evaluate the shear bond strength and adhesive remnant index ARI) of orthodontic brackets following enamel conditioning with acid etching, hydroabrasion, and with both procedures. Thirty extracted human premolars were divided into three groups and received either acid etching, hydroabrasion or both procedures. Orthodontic brackets were bonded with composite resin. Shear bond strength was tested with a tensile machine, then the teeth were observed under a stereomicroscope to evaluate ARI scores. The enamel morphology after each conditioning method was evaluated with scanning electron microscope imaging. A one-way ANOVA and a Kruskal-Wallis H test were used to compare the bond strength and the ARI scores among the three groups. Hydroabrasion alone produced shear bond strength values below clinical acceptability, while the combination of acid etching and hydroabrasion produced the highest values. The ARI scores in the hydroabrasion group were significantly different from the other groups. Hydroabrasion followed by acid etching was effective in increasing the shear bond strength of orthodontic brackets. Further in vivo studies are needed to confirm the cost and benefits of this technique.

2.
Prog Orthod ; 21(1): 32, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32924097

RESUMO

BACKGROUND: The loss of third-order information in pre-adjusted brackets due to torsional play is a problem in clinical orthodontics. The aim of this study was to evaluate the impact of slot height, archwire height, width and edge bevel's radius on the torsional play for three brackets/archwire systems. METHODS: Ninety brackets with a 0.022 × 0.028 in. slot with McLaughlin-Bennett-Trevisi prescription from three different manufacturers were selected, and the slot's height and depth were measured using a profile projector. Sixty stainless-steel rectangular archwires from three different manufacturers were sectioned and observed with a SEM to measure their height, width, and radius of edge bevel. The recorded data were used to calculate the theoretical torsional play between different slot-archwire combinations. One-way ANOVA was used to compare the measurements within different bracket types and among different manufacturers. RESULTS: Slot height was usually oversized. Archwire's height was usually undersized, but oversized wires were also observed. The radius edge bevel was the most variable parameter. A certain degree of torsional play is always present that differs from one bracket type to another of the same producer and that can even be doubled from one manufacturer to another. CONCLUSIONS: Due to production tolerance, differences between the nominal values and the real dimensions of any components of a slot/archwire system are common. This results in a torsional play that limits torque expression. The archwire's edge bevel plays an important role in torque expression, and clearer information should be provided by the manufacturers regarding this aspect.


Assuntos
Braquetes Ortodônticos , Fios Ortodônticos , Desenho de Aparelho Ortodôntico , Aço Inoxidável , Torque
3.
Cranio ; 38(5): 342-350, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30332921

RESUMO

OBJECTIVE: To compare morphologic findings in MRI and skeletal divergence of a group of patients with temporomandibular joint disorders (TMD) subdivided into condylar symmetric and asymmetric. METHODS: Fifty-nine adults (26.7 years old) with TMD were retrospectively recruited. Condylar height symmetry was evaluated by orthopantomography (Habets's method) and used to divide patients into Symmetric and Asymmetric groups; skeletal divergence was assessed on lateral cephalograms. MRI was used to evaluate the condylar long axis' angle, the glenoid fossa morphology, and the degree of disc displacement. RESULTS: Asymmetric subjects showed a hyperdivergent skeletal pattern (p = 0.036), asymmetric condylar long axis (p = 0.018), and deeper (p = 0.025) and asymmetric (p = 0.001) glenoid fossa compared to symmetric subjects. CONCLUSION: Patients with TMD and condylar asymmetry diagnosed with orthopantomography are more likely to show hyperdivergent skull in cephalometry, condylar asymmetry of both height and major axis, and a steeper glenoid fossa in MRI.


Assuntos
Transtornos da Articulação Temporomandibular , Articulação Temporomandibular , Adulto , Cefalometria , Humanos , Imagem por Ressonância Magnética , Côndilo Mandibular , Estudos Retrospectivos
4.
Dent Mater J ; 39(3): 367-374, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31827057

RESUMO

The aim of the present study was to evaluate how hydroabrasion performs during composite removal. A standardized amount of composite was bonded to 40 enamel surfaces of extracted third molars, then removed with either a tungsten carbide bur mounted on a micro-motor handpiece without irrigation, a tungsten carbide bur mounted on a micro-motor handpiece with irrigation, a tungsten carbide bur mounted on an air-rotor handpiece, or hydroabrasion. The four treatment methods were compared using the enamel-surface-index and the adhesive-remnant-index and performing a Kruskal-Wallis statistical test to detect differences between each method' scores. Hydroabrasion produced significantly less damage to the enamel surface compared to the other three methods. Hydroabrasion was the cleaning method that produced less damages to the enamel surface, at a cost of a less efficient composite removal than tungsten carbide burs on micro-motor handpiece.


Assuntos
Descolagem Dentária , Braquetes Ortodônticos , Cimentos Dentários , Esmalte Dentário , Propriedades de Superfície
5.
Sci Rep ; 9(1): 19309, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31848435

RESUMO

The aim of this study was to evaluate the differences in sella dimensions and shape between growing patients with Class I, Class II, and Class III skeletal malocclusions, evaluated through morphometric analysis. Seventy-eight subjects aged between 9 and 13 years were selected and assigned to either the Class I, Class II, or Class III groups according to the measured ANB angle (the angle between the Nasion, skeletal A-point and skeletal B-point). Six landmarks were digitised to outline the shape of the sella turcica. Linear measurements of the sella length and depth were also performed. Procrustes superimposition, principal component analysis, and canonical variate analysis were used to evaluate the differences in sella shape between the three groups. A one-way MANOVA and Tukey's or Games-Howell tests were used to evaluate the presence of differences in sella dimensions between the three groups, gender, and age. The canonical variate analysis revealed a statistically significant difference in sella shape between the Class I and the Class II groups, mostly explained by the CV1 axis and related to the posterior clinoidal process and the floor of the sella. No differences were found regarding linear measurements, except between subjects with different age. These differences in sella shape, that are present in the earlier developmental stages, could be used as a predictor of facial growth, but further studies are needed.


Assuntos
Má Oclusão de Angle Classe III/diagnóstico por imagem , Má Oclusão de Angle Classe II/diagnóstico por imagem , Má Oclusão de Angle Classe I/diagnóstico por imagem , Sela Túrcica/diagnóstico por imagem , Adolescente , Fatores Etários , Pesos e Medidas Corporais/métodos , Cefalometria/métodos , Criança , Feminino , Humanos , Masculino , Má Oclusão de Angle Classe I/fisiopatologia , Má Oclusão de Angle Classe II/fisiopatologia , Má Oclusão de Angle Classe III/fisiopatologia , Análise de Componente Principal , Sela Túrcica/fisiopatologia
6.
Orthod Craniofac Res ; 22(4): 236-247, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31207100

RESUMO

OBJECTIVES: To evaluate whether changes in the concentration of different biomarkers in the gingival crevicular fluid (GCF) can be used to detect the root resorption process in adult or adolescent patients undergoing treatment with a fixed appliance, in comparison with untreated subjects or treated patients not showing signs of root resorption. MATERIAL AND METHODS: The following databases were analysed in the period between June 2017 and March 2018, without any language and initial date restrictions: PubMed, EMBASE, Scopus, Web of Science and Cochrane Library. A quality assessment instrument (QAI) was developed to establish the risk of bias. RESULTS: A total of 1127 articles were analysed. Based on the inclusion and exclusion criteria, seven studies qualified for the final review. The QAI tool revealed that five articles were at a moderate risk of bias and two articles were at a low risk of bias. CONCLUSION: Dentine phosphoprotein (DPP) may be considered a relatively useful marker for root resorption. Dentinal sialoprotein (DSP) could be a potential biomarker but is not highly helpful at detecting root shortening. Inflammatory cytokines (pro- and anti-resorption), osteopontin (OPN), osteoprotegerin (OPG), RANKL and alkaline phosphatase (ALP) are useful biomarkers to explain the biological mechanisms that occur during orthodontic movement but are not specific enough. Further studies are required to clarify the role of GM-CSF as a potential biomarker to distinguish subjects at a risk of severe root resorption in the early phase.


Assuntos
Reabsorção da Raiz , Adolescente , Adulto , Biomarcadores , Citocinas , Líquido do Sulco Gengival , Humanos , Técnicas de Movimentação Dentária
7.
Minerva Stomatol ; 68(3): 118-125, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31014061

RESUMO

BACKGROUND: The soft tissue profile outcome after functional treatment of Class II malocclusion is important for a patient's aesthetic and psychosocial results. The soft tissue effects of the Sander bite-jumping appliance (BJA), which is the device that produces the greatest mandibular advancement according to a systematic review, have never been investigated. The aim of the present study was to assess the soft tissue effects of the BJA in comparison to matched untreated controls. METHODS: A total of 19 patients treated with BJA during puberty were retrospectively recruited, and 15 untreated controls were retrieved from a previous growth study to match the treated group. Lateral cephalograms were used to evaluate the pre- and post-treatment differences in the ANB angle, the inclination of the upper and lower incisors, facial convexity, the nasolabial angle and the sagittal position of the skeletal and soft tissue at points A and B. Independent t-tests or Mann-Whitney U tests were used to detect differences between the two groups. RESULTS: Statistically significant differences were found for the ANB angle, the inclination of the upper incisors and facial convexity. CONCLUSIONS: Functional treatment of Class II patients with the Sander BJA during puberty was effective at improving the profile and reducing the facial convexity angle in the short term.


Assuntos
Má Oclusão de Angle Classe II , Maxila , Cefalometria , Estética Dentária , Humanos , Mandíbula , Estudos Retrospectivos , Resultado do Tratamento
8.
J Clin Exp Dent ; 10(9): e869-e875, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30386519

RESUMO

Background: The aim of the present study was to evaluate if the different muscular activity correlated to different degrees of facial divergence has an effect on the time needed to extrude a palatally impacted maxillary canine. Material and Methods: Twenty-six patients were retrospectively selected, all treated with a specific cantilever appliance that allows extrusion of the impacted canine applying a physiologic amount of force below 0.6 N in a predictable way. For all the patients, pre-treatment cephalometric tracings were used to evaluate facial divergence through the FMA angle, the angle between the maxillary and mandibular plane, and the angles between the occlusal plane and either the maxillary and mandibular plane. Linear bivariate regression was calculated to evaluate if facial divergence can predict the time needed for canine extrusion. Results: The linear regression model was not able to predict extrusion time from variables explaining the facial divergence. Conclusions: Palatally impacted maxillary canines can be treated with the application of physiologic extrusion force regardless of patients' facial divergence and muscular activity. Key words:Impacted canines, cantilever, facial divergence, muscular activity.

9.
Dental Press J Orthod ; 23(5): 39.e1-39.e13, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30427499

RESUMO

INTRODUCTION: The selection of appropriate sites for miniscrew insertion is critical for clinical success. OBJECTIVES: The aim of the present study was to evaluate how interradicular spaces measured on panoramic radiograph compare with Cone-Beam Computed Tomography (CBCT), and how crowding can influence the presence of available space for miniscrew insertion, in order to define a new "safe zones" map. METHODS: A total of 80 pre-treatment panoramic radiographs and 80 CBCT scans with corresponding digital models were selected from the archives of the department of Dentistry, Aarhus University. Crowding was measured on digital models, while interradicular spaces mesial to the second molars were measured on panoramic radiographs and CBCTs. For panoramic radiographs, a magnification factor was calculated using tooth widths measured on digital models. Statistical analyses were performed to investigate the correlation between the amount of crowding and the available interradicular space. Visual maps showing the amount of interradicular spaces measured were drawn. RESULTS: The most convenient interradicular spaces are those between the second molar and the first premolar in the mandible, and between the central incisors in the maxilla. However, some spaces were revealed to be influenced by crowding. CONCLUSIONS: Calibration of panoramic radiographs is of utmost importance. Generally, panoramic radiographs underestimate the available space. Preliminary assessment of miniscrew insertion feasibility and the related selection of required radiographs can be facilitated using the new "safe zone" maps presented in this article.


Assuntos
Parafusos Ósseos , Arco Dental/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Procedimentos de Ancoragem Ortodôntica/métodos , Adolescente , Adulto , Calibragem , Criança , Tomografia Computadorizada de Feixe Cônico , Arco Dental/anatomia & histologia , Implantação Dentária/métodos , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Dente Molar/anatomia & histologia , Radiografia Panorâmica , Estudos Retrospectivos , Adulto Jovem
10.
Dental press j. orthod. (Impr.) ; 23(5): 39.e1-39.e13, Sept.-Oct. 2018. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-975019

RESUMO

Abstract Introduction: The selection of appropriate sites for miniscrew insertion is critical for clinical success. Objectives: The aim of the present study was to evaluate how interradicular spaces measured on panoramic radiograph compare with Cone-Beam Computed Tomography (CBCT), and how crowding can influence the presence of available space for miniscrew insertion, in order to define a new "safe zones" map. Methods: A total of 80 pre-treatment panoramic radiographs and 80 CBCT scans with corresponding digital models were selected from the archives of the department of Dentistry, Aarhus University. Crowding was measured on digital models, while interradicular spaces mesial to the second molars were measured on panoramic radiographs and CBCTs. For panoramic radiographs, a magnification factor was calculated using tooth widths measured on digital models. Statistical analyses were performed to investigate the correlation between the amount of crowding and the available interradicular space. Visual maps showing the amount of interradicular spaces measured were drawn. Results: The most convenient interradicular spaces are those between the second molar and the first premolar in the mandible, and between the central incisors in the maxilla. However, some spaces were revealed to be influenced by crowding. Conclusions: Calibration of panoramic radiographs is of utmost importance. Generally, panoramic radiographs underestimate the available space. Preliminary assessment of miniscrew insertion feasibility and the related selection of required radiographs can be facilitated using the new "safe zone" maps presented in this article.


Resumo Introdução: a seleção de locais apropriados para a inserção de mini-implantes é crítica para o sucesso clínico. Objetivo: os objetivos do presente estudo foram avaliar as medições de espaços inter-radiculares feitas em radiografias panorâmicas e compará-las com as medições feitas com tomografia computadorizada de feixe cônico (TCFC), além de avaliar como o apinhamento pode influenciar na disponibilidade de espaços para inserção dos mini-implantes, no intuito de definir um novo mapa de "áreas seguras". Métodos: foram selecionadas, nos arquivos do departamento de Ortodontia da Aarhus University, 80 radiografias panorâmicas pré-tratamento e 80 imagens de TCFC com os modelos digitais correspondentes. O apinhamento foi medido nos modelos digitais, enquanto os espaços inter-radiculares mesiais aos segundos molares foram medidos nas radiografias panorâmicas e na TCFC. O fator de magnificação das radiografias panorâmicas foi calculado utilizando-se as larguras dentárias medidas nos modelos digitais. Análises estatísticas foram realizadas para investigar a correlação entre a quantidade de apinhamento e o espaço inter-radicular disponível. Foram desenhados mapas visuais mostrando a quantidade dos espaços inter-radiculares medidos. Resultados: os espaços inter-radiculares mais adequados são aqueles entre o segundo molar e o primeiro pré-molar inferior, e entre os incisivos centrais superiores. Porém, verificou-se que alguns espaços são influenciados pelo apinhamento. Conclusões: A calibração das radiografias panorâmicas é de suma importância, pois, geralmente, as radiografias panorâmicas subestimam o espaço disponível. A avaliação preliminar da viabilidade de inserção dos mini-implantes e a seleção das radiografias necessárias para isso podem ser facilitadas utilizando-se os novos mapas de "áreas seguras" aqui apresentados.

11.
Am J Orthod Dentofacial Orthop ; 154(1): 55-64, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29957320

RESUMO

INTRODUCTION: Orthodontic extrusion of impacted maxillary canines requires careful biomechanical planning and the use of physiologic force. The aim of this study was to evaluate the time needed for orthodontic extrusion of impactions of different severities, using a device that can predictably apply forces under 0.6 N. METHODS: Twenty-two patients who were consecutively treated were selected retrospectively, and a total of 30 impacted canines were studied. Indexes of impaction were used to measure severity on pretreatment panoramic radiographs. Statistical analysis was used to detect interactions between treatment time, complexity of impaction, age, and sex. RESULTS: Treatment time was highly dependent on the patient's age; the shortest treatment time was observed in 11- to 12-year old patients. On the other hand, the severity of impaction had no effect on treatment time. CONCLUSIONS: Applying physiologic force with the proposed device resulted in a short treatment time, which depended on the patient's age more than the impaction complexity. Few complications were associated with use of this device. Future prospective studies are needed to replicate these findings and confirm the recommended use of this device.


Assuntos
Dente Canino , Extrusão Ortodôntica/instrumentação , Dente Impactado/terapia , Adolescente , Adulto , Criança , Estudos de Coortes , Desenho de Equipamento , Feminino , Humanos , Masculino , Maxila , Extrusão Ortodôntica/métodos , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
12.
Prog Orthod ; 19(1): 17, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29911278

RESUMO

BACKGROUND: The present systematic review was carried out to determine the correlation between gingival recession/bone height and incisor inclination in non-growing post-orthodontic patients compared to adult untreated subjects or patients treated with different methodologies. MATERIALS AND METHODS: PubMed, EMBASE, Web of Science, Scopus, Cochrane, and OpenGrey databases were searched without time and language restriction. Search terms included orthodontic, incisor, inclination, angulation, proclination, and gingival. Articles involving human participants and adult subjects receiving orthodontic treatment with fixed appliance, having incisors position, bone height and/or gingival recessions evaluated pre- and post-treatment were included. Two authors independently extracted data using predefined forms. Risk of bias in individual studies was assessed with the Newcastle-Ottawa Scale. RESULTS: Two observational studies were included in the qualitative analysis. The heterogeneity in outcome assessment among the studies did not allow performing a meta-analysis. The two studies, while observing some effects of orthodontic treatment on the development of gingival recession, reported that these effects were not statistically or clinically significant. CONCLUSIONS: There is no strong scientific evidence concluding that proclination of incisors by means of fixed orthodontic appliances can affect periodontal health. Further prospective studies are required to elucidate this statement. PROTOCOL: PROSPERO database registration number CRD42016042369 .


Assuntos
Retração Gengival/etiologia , Incisivo/fisiopatologia , Técnicas de Movimentação Dentária/efeitos adversos , Humanos , Mandíbula
13.
J Clin Exp Dent ; 10(3): e241-e247, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29721225

RESUMO

Background: To evaluate how the amount of expansion of the primary second molars, the patient's age, and the skeletal maturation stage influence the amount of expansion at the level of the permanent first molars. Material and Methods: Fifty-five patients aged between 6 and 11 years with a cervical vertebral maturation stage of CS1 or CS2 were retrospectively selected. The intermolar width was measured before and after expansion to evaluate the amount of expansion achieved at the level of the primary second molars and the permanent first molars. Stepwise multiple linear regression was used to evaluate how the amount of primary molars expansion, the patient's age, and the cervical vertebral maturation stage predict the amount of permanent molar expansion. Results: A significant regression equation was found, and for every 1 mm of primary molar expansion, 0.91 mm of permanent molar expansion can be expected. An age between 6 and 11 years and the CS1 or CS2 skeletal maturation stage were not significant predictors of permanent molar expansion. Conclusions: A rapid maxillary expansion appliance anchored on primary second molars is effective in expanding the permanent molars to correct a transverse maxillary deficiency in prepubertal patients, transferring the risks associated with the large forces used to the primary teeth. Key words:Maxillary expansion, transversal deficiency, primary molars.

14.
Prog Orthod ; 19(1): 9, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29607469

RESUMO

BACKGROUND: Clear aligner treatment offers several advantages, but the available literature shows that some kind of tooth movements are unpredictable. In addition, the majority of the studies are focused on one clear aligner system, while different characteristics of various systems can provide different treatment outcomes. The aim of the present retrospective cohort study was to evaluate the predictability of Nuvola® aligner system in achieving torque movements of anterior teeth. METHODS: Thirty-nine adult patients, who were consecutively treated with clear aligners, were retrospectively selected, and digital models pre-treatment (T0), post-treatment (T1) and the digital setup models (TS) were collected. Only the first phase of treatment made of 12 aligners was considered for the present study. Torque of anterior teeth was measured as labiolingual inclination on digital models at T0, T1, and TS using VAM software. Any difference between the predicted and achieved torque movements was evaluated using Wilcoxon signed-rank test or paired sample t test. First-type error was set as p < 0.008. RESULTS: No statistically significant difference was found for all the anterior teeth between predicted and achieved torque movements. CONCLUSIONS: The studied clear aligner system was able to produce clinical outcomes comparable to the planning of the digital setup relative to torque movements of the anterior teeth.


Assuntos
Má Oclusão/terapia , Aparelhos Ortodônticos Removíveis , Técnicas de Movimentação Dentária , Adulto , Modelos Dentários , Feminino , Humanos , Incisivo , Masculino , Desenho de Aparelho Ortodôntico , Estudos Retrospectivos , Torque , Resultado do Tratamento
15.
Am J Otolaryngol ; 39(4): 388-391, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29625769

RESUMO

PURPOSE: To evaluate if Body Mass Index (BMI) is correlated to Apnea-Hypopnea Index (AHI), mean arterial oxygen saturation (SaO2) and Nadir SaO2, which are all indexes defining the severity of the respiratory stress associated with Obstructive Sleep Apnea (OSA). MATERIALS AND METHODS: Seventy-five adult patients (mean age 51.4) referred for polysomnography were retrospectively recruited. BMI was calculated for each patient, as well as AHI, SaO2, and Nadir SaO2 recorded during polysomnography. Spearman's Rho test was used to evaluate if OSA severity was correlated to BMI values. First type error was set as p < 0.025. RESULTS: No correlation was observed between BMI and AHI, and between BMI and SaO2. A statistically significant negative correlation (r2 = 0.424; p < 0.001) was found between the BMI index and the Nadir SaO2. CONCLUSIONS: Higher BMI values were correlated with lower Nadir SaO2 during overnight polysomnography. Since hypoxia stress is a risk factor for cardiovascular diseases and alters the lipid metabolism, dietary consulting should be recommended in association with other treatment modalities for OSA.


Assuntos
Índice de Massa Corporal , Obesidade/complicações , Obesidade/diagnóstico , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/etiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
16.
J Craniofac Surg ; 29(3): e262-e267, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29554061

RESUMO

INTRODUCTION: Temporomandibular disease (TMD) etiology is multifactorial and is related to many perpetuating, predisposing, and initiating factors. The daytime parafunctions may have an important role in TMD pathogenesis. The most frequent parafunctions analyzed were the static parafunction (ie, clenching) and the dynamic parafunction (ie, grinding). In the present paper, the authors evaluated the swallowing (an oral function/parafunction) with the surface electromyography in patients with TMD. MATERIALS AND METHODS: Twenty patients with TMD problems (nonhealthy patients, NHP) (mean age: 33 ±â€Š1.994; 8 men and 12 women) and 20 healthy matched subjects (HP) (34.4 ±â€Š2.782; 6 men and 14 women) were selected and examined. On each patient, an 8-channel surface electromyography was done during saliva swallowing. RESULTS: Nonhealthy patients presented higher masseter and temporalis activation (P < 0.05) and an unbalancing of temporalis and submental muscles activation (P < 0.05) than the HP. DISCUSSION: Nonhealthy patients presented a time of swallow higher than HP (P < 0.001). Nonhealthy patients presented a higher muscles activation and time of swallow than HP and a decrease of muscles balancing activation.


Assuntos
Transtornos de Deglutição , Transtornos da Articulação Temporomandibular , Adulto , Humanos
17.
Am J Orthod Dentofacial Orthop ; 153(2): 195-203, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29407496

RESUMO

INTRODUCTION: Orthodontic treatment of palatally impacted maxillary canines raises many difficulties; to minimize complications, careful planning of orthodontic extrusion and the use of physiologic force are crucial. The aim of this study was to quantitatively evaluate a simple and reproducible system for orthodontic extrusion of impacted canines that can provide the correct amount of force. METHODS: Ten specimens were constructed, consisting of a cantilever made with a 0.6-mm or 0.7-mm stainless steel wire modeled around a transpalatal bar with 3, 5, or 7 loops in the shape of a helical torsion spring. A mechanical testing machine was used to measure the force produced by the cantilever at 3, 6, 9, 12, and 15 mm of activation. RESULTS: The force values ranged from 1.24 ± 0.13 N for the 0.7-mm wire with 3 loops to 0.48 ± 0.04 N for the 0.6-mm wire with 7 loops. The forces measured for the 0.6-mm wire with 3 loops and the 0.7-mm wire with 7 loops were similar at 15 mm of deflection. CONCLUSIONS: The proposed system has a simple and robust design, is easy to construct and manage, and can provide the desired amount of force by changing the wire diameter and number of loops.


Assuntos
Dente Canino/cirurgia , Extrusão Ortodôntica/métodos , Dente Impactado/cirurgia , Análise do Estresse Dentário , Humanos , Maxila , Extrusão Ortodôntica/instrumentação , Fios Ortodônticos
18.
Plant Cell Environ ; 41(3): 661-674, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29314044

RESUMO

Abortion of fertilized ovaries at the tip of the ear can generate significant yield losses in maize crops. To investigate the mechanisms involved in this process, 2 maize hybrids were grown in field crops at 2 sowing densities and under 3 irrigation regimes (well-watered control, drought before pollination, and drought during pollination), in all possible combinations. Samples of ear tips were taken 2-6 days after synchronous hand pollination and used for the analysis of gene expression and sugars. Glucose and fructose levels increased in kernels with high abortion risk. Several FASCICLIN-LIKE ARABINOGALACTAN PROTEIN (FLA) genes showed negative correlation with abortion. The expression of ZmFLA7 responded to drought only at the tip of the ear. The abundance of arabinogalactan protein (AGP) glycan epitopes decreased with drought and pharmacological treatments that reduce AGP activity enhanced the abortion of fertilized ovaries. Drought also reduced the expression of AthFLA9 in the siliques of Arabidopsis thaliana. Gain- and loss-of-function mutants of Arabidopsis showed a negative correlation between AthFLA9 and seed abortion. On the basis of gene expression patterns, pharmacological, and genetic evidence, we propose that stress-induced reductions in the expression of selected FLA genes enhance abortion of fertilized ovaries in maize and Arabidopsis.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Mucoproteínas/genética , Proteínas de Plantas/genética , Sementes/fisiologia , Zea mays/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Quimera , Secas , Glucosídeos/farmacologia , Mucoproteínas/metabolismo , Óvulo Vegetal/genética , Óvulo Vegetal/fisiologia , Floroglucinol/análogos & derivados , Floroglucinol/farmacologia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Polinização , Sementes/genética , Zea mays/efeitos dos fármacos , Zea mays/fisiologia
19.
Dental Press J Orthod ; 22(5): 90-97, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29160349

RESUMO

OBJECTIVE: To define a map of interradicular spaces where miniscrew can be likely placed at a level covered by attached gingiva, and to assess if a correlation between crowding and availability of space exists. METHODS: Panoramic radiographs and digital models of 40 patients were selected according to the inclusion criteria. Interradicular spaces were measured on panoramic radiographs, while tooth size-arch length discrepancy was assessed on digital models. Statistical analysis was performed to evaluate if interradicular spaces are influenced by the presence of crowding. RESULTS: In the mandible, the most convenient sites for miniscrew insertion were in the spaces comprised between second molars and first premolars; in the maxilla, between first molars and second premolars as well as between canines and lateral incisors and between the two central incisors. The interradicular spaces between the maxillary canines and lateral incisors, and between mandibular first and second premolars revealed to be influenced by the presence of dental crowding. CONCLUSIONS: The average interradicular sites map hereby proposed can be used as a general guide for miniscrew insertion at the very beginning of orthodontic treatment planning. Then, the clinician should consider the amount of crowding: if this is large, the actual interradicular space in some areas might be significantly different from what reported on average. Individualized radiographs for every patient are still recommended.


Assuntos
Parafusos Ósseos , Implantação Dentária Endo-Óssea/métodos , Má Oclusão , Procedimentos de Ancoragem Ortodôntica/instrumentação , Simulação por Computador , Modelos Dentários , Humanos , Processamento de Imagem Assistida por Computador , Radiografia Panorâmica
20.
Dental press j. orthod. (Impr.) ; 22(5): 90-97, Sept.-Oct. 2017. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-891094

RESUMO

ABSTRACT Objective: To define a map of interradicular spaces where miniscrew can be likely placed at a level covered by attached gingiva, and to assess if a correlation between crowding and availability of space exists. Methods: Panoramic radiographs and digital models of 40 patients were selected according to the inclusion criteria. Interradicular spaces were measured on panoramic radiographs, while tooth size-arch length discrepancy was assessed on digital models. Statistical analysis was performed to evaluate if interradicular spaces are influenced by the presence of crowding. Results: In the mandible, the most convenient sites for miniscrew insertion were in the spaces comprised between second molars and first premolars; in the maxilla, between first molars and second premolars as well as between canines and lateral incisors and between the two central incisors. The interradicular spaces between the maxillary canines and lateral incisors, and between mandibular first and second premolars revealed to be influenced by the presence of dental crowding. Conclusions: The average interradicular sites map hereby proposed can be used as a general guide for miniscrew insertion at the very beginning of orthodontic treatment planning. Then, the clinician should consider the amount of crowding: if this is large, the actual interradicular space in some areas might be significantly different from what reported on average. Individualized radiographs for every patient are still recommended.


RESUMO Objetivo: elaborar um mapa dos espaços inter-radiculares nos quais os mini-implantes podem ser inseridos, em um nível coberto por gengiva inserida; e avaliar se existe correlação entre o apinhamento dentário e a disponibilidade de espaços. Métodos: radiografias panorâmicas e modelos digitais de 40 pacientes foram selecionados seguindo critérios de inclusão. Os espaços inter-radiculares foram medidos nas radiografias panorâmicas, enquanto a discrepância de modelo foi avaliada nos modelos digitais. Realizou-se, então, uma análise estatística para avaliar se os espaços inter-radiculares foram influenciados pela presença do apinhamento dentário. Resultados: na mandíbula, os locais mais adequados para a inserção dos mini-implantes foram os espaços compreendidos entre os segundos molares e primeiros pré-molares; na maxila, entre os primeiros molares e segundos pré-molares, bem como entre caninos e incisivos laterais, e entre os dois incisivos centrais. Os espaços inter-radiculares entre os caninos e incisivos laterais superiores e entre o primeiro e o segundo pré-molares inferiores mostraram-se influenciados pela presença do apinhamento dentário. Conclusões: o mapa dos espaços inter-radiculares mais adequados aqui proposto pode ser adotado como um guia geral para a inserção de mini-implantes, e pode ser usado logo ao início do planejamento do tratamento ortodôntico. Em seguida, o clínico deve levar em consideração a quantidade de apinhamento: caso esse seja grande, o real espaço inter-radicular, em algumas áreas, poderá ser significativamente diferente da média aqui relatada. Assim, recomenda-se que sempre sejam feitas radiografias individualizadas para cada paciente.

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